SHOULDER PIECE (Heb. kathēph)
That part of the ephod where the front and the back were joined together, making the garment to be of one piece (Exod.28.7-Exod.28.8).The piece of meat that is taken from the shoulder of the animal (Ezek.24.4).
International Standard Bible Encyclopedia (1915)
The word designates the two straps or pieces of cloth which passed from the back of the ephod (see Ephod) of the high priest over the shoulder and were fastened at the front. These shoulder-pieces seem to have been made of a precious texture of linen (or byssos) with threads of gold, blue, purple and scarlet, to which two onyx (or beryl) stones were attached bearing the names of six tribes of Israel each. These are called the "stones of memorial" (Ex 39:18). On these straps there were also fastened the plaited or woven bands ("wreathed chains") from which, by means of two golden rings, the breastplate was suspended. It is by no means clear from the descriptions (Ex 28:7,12,25; 39:4,7,18,20) how we have to imagine the form and attachment of these shoulder-pieces. It has been thought that the ephod might be of Egyptian origin, which is not very probable, though V. Ancessi, Annales de philosophie chretienne, 1872, 45 ff, reproduces some representations from the great work of Lepsius, Denkmaler, where costly royal garments have two shoulder straps, like the ephod. Usually Egyptian garments have no shoulder strap, or at most one.